The present disclosure relates generally to an apparatus and method for detecting gamma ray radiation, more particularly to an apparatus and method for petroleum reservoir formation identification and the application of gamma ray detection for the characterization thereof, and even more particularly to an apparatus and method for determining sand shale laminations in earth formations in cased well bores.
Current petrophysical trends place large importance on determining laminated sand shale sequences from poorer quality rocks such as dispersed clay sands, as laminated zones are possible production targets for petroleum-based products, while dispersed clay sand zones are not. Conventional analysis techniques applied to these laminated sands may lead to an underestimation of net pay and productivity. In an open-hole environment, lamination detection is straight forward, but in a cased-hole environment, lamination detection is not so straight forward. Accordingly, there is a need in the art for improved lamination detection techniques suitable for use in a cased-hole environment.